Designation: A 307 – 03Standard Specification for Carbon Steel Bolts and Studs, 60 000 PSI Tensile Strength1 This standard is issued under the fixed designation A 307; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense. fication A 563, Table 3) greater than the specified grade and style of nut are also suitable. 1. Scope* 1.1 This specification2 covers the chemical and mechanical requirements of three grades of carbon steel bolts and studs in sizes 1⁄4 in. (6.35 mm) through 4 in. (104 mm). The fasteners are designated by “Grade” denoting tensile strength and intended use, as follows: Grade Grade A Grade B Grade C 1.4 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 Supplementary Requirement S1 of an optional nature is provided, which describes additional restrictions to be applied when bolts are to be welded. It shall apply only when specified in the inquiry, order, and contract. 1.6 Terms used in this specification are defined in Specification F 1789 unless otherwise defined herein. Description Bolts and studs having a minimum tensile strength of 60 ksi (414 MPa) and intended for general applications, Bolts and studs having a tensile strength of 60 to 100 ksi (414 to 690 MPa) and intended for flanged joints in piping systems with cast iron flanges, and Nonheaded anchor bolts, either bent or straight, having properties conforming to Specification A 36 (tensile strength of 58 to 80 ksi (400 to 550 MPa)) and intended for structural anchorage purposes. 2. Referenced Documents 2.1 ASTM Standards: A 36/A 36M Specification for Carbon Structural Steel3 A 153/A 153M Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware4 A 370 Test Methods and Definitions for Mechanical Testing of Steel Products5 A 563 Specification for Carbon and Alloy Steel Nuts6 A 706/A 706M Specification for Low-Alloy Steel Deformed Bars for Concrete Reinforcement3 A 751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products5 B 695 Specification for Coatings of Zinc Mechanically Deposited on Iron and Steel7 D 3951 Practice for Commercial Packaging8 F 606 Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, and Rivets6 F 1470 Guide for Fastener Sampling for Specified Mechanical Properties and Performance Inspection6 F 1789 Terminology for F16 Mechanical Fasteners6 2.2 ANSI/ASME Standards: B 1.1 Unified Screw Threads9 1.1.1 The term studs includes stud stock, sometimes referred to as threaded rod. 1.2 This specification does not cover requirements for machine screws, thread cutting/forming screws, mechanical expansion anchors or similar externally threaded fasteners. 1.3 Suitable nuts are covered in Specification A 563. Unless otherwise specified, the grade and style of nut for each grade of fastener, of all surface finishes, shall be as follows: Fastener Grade and Size A, C, 1⁄4 to 11⁄2 in. A, C, over 11⁄2 to 4 in. B, 1⁄4 to 4 in. A Nut Grade and StyleA A, hex A, heavy hex A, heavy hex Nuts of other grades and styles having specified proof load stresses (Speci- 3 Annual Book of ASTM Standards, Vol 01.04. Annual Book of ASTM Standards, Vol 01.06. 5 Annual Book of ASTM Standards, Vol 01.03. 6 Annual Book of ASTM Standards, Vol 01.08. 7 Annual Book of ASTM Standards, Vol 02.05. 8 Annual Book of ASTM Standards, Vol 15.09. 9 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036. 1 4 This specification is under the jurisdiction of ASTM Committee F16 on Fasteners and is the direct responsibility of Subcommittee F16.02 on Steel Bolts, Nuts, Rivets, and Washers. Current edition approved Oct. 1, 2003. Published October 2003. Originally approved in 1947. Last previous edition approved in 2002 as A 307 – 02. 2 For ASME Boiler and Pressure Vessel Code applications see related Specification SA-307 in Section II of that Code. *A Summary of Changes section appears at the end of this standard. Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States. 1 4.3 In case of conflict or for referee purposes.1 Steel for bolts and studs shall be made by the openhearth. 11 Available from Standardization Documents Order Desk.24. 5. that is.8 Other Finishes—Specify other protective finish. Practices.1 Grades A and B bolts and studs shall conform to the hardness specified in Table 2.1 ASTM designation and year of issue.1.1. 3. other than those excepted in 6.2). A. Bldg. that is. or C.10 Specify if certified test report is required (see 8. 4. max Manganese. 4. the product analysis shall take precedence.041 0.1. mechanically deposited.2 Name of product.5.1. in diameter or less.3 Military Standard: MIL-STD 105 Single Sampling Plan for Normal Inspection11 4. NY 10016-5990. Threaded components (bolts and nuts) shall be coated by the same zinc-coating process and the supplier’s option is limited to one process per item with no mixed processes in a lot. 4. or no preference.3.051 A A Resulfurized steel is not subject to rejection based on product analysis for sulfur.6 Chemical analyses shall be performed in accordance with Test Methods. 3. 5. shall preferably be tested full size and when equipment of sufficient capacity is available and shall conform to the requirements for tensile strength specified in Table 3. PA 19111-5094. 6.1 Part Identifying Number (PIN) Code System10 2.1. 4. Mechanical Properties 6. which shall conform to the product analysis specified in Table 1. or lead has been intentionally added shall not be permitted for Grade B bolts and studs. ASME International Headquarters.4 When no preference is specified. the supplier may furnish either a hot-dip zinc coating in accordance with Specification A 153. 3. and 3.1.12 For establishment of a part identifying system.2 Bolts shall be produced by hot or cold forging of the heads or machining from bar stock.2. Attn: NPODS.5. 3. or electric-furnace process. Class 50.1 Square and Hex Bolts and Screws9 B 18. Hot-Dip and Mechanically Deposited: 4.3.90 0.2 Grade A and B bolts and studs 1½ in. the fasteners shall be zinc-coated by the mechanical-deposition process in accordance with the requirements of Class 50 of Specification B 695. max Phosphorus. 3. for example. the fasteners shall be zinc-coated by the hot-dip process in accordance with the requirements of Class C of Specification A 153.1. 6.1 Cold headed fasteners with head configurations other than hex shall be stress relief annealed. 4. for example hot dip. hex or heavy hex. 3. basic-oxygen. mechanically deposited. Ordering Information 3. 6. bolts or studs. TABLE 1 Chemical Requirements for Grades A and B Bolts and Studs Carbon.1 Orders for externally threaded fasteners (including nuts and accessories) under this specification shall include the following: 3. Three Park Ave. or when the length of the bolt makes full-size testing impractical. 5.9 Specify if inspection at point of manufacture is required.1. or no preference (see 4. max Grade A Grade B 10 Available from American Society of Mechanical Engineers (ASME). 700 Robbins Ave. or B. and Terminology A 751. When equipment of sufficient capacity for full-size bolt testing is not available. tellurium. see ANSI/ASME B18.93 0. 3. If no grade is specified. Chemical Composition 5. Heat Analysis 0. 3. and bolt head style.4.11 Specify additional testing (8.4 Bolt and stud threads shall be rolled or cut. hot-dip. Grade A is furnished.5 Grade C nonheaded anchor bolts shall be tested using machined specimens and shall conform to the tensile properties specified for bars in Specification A 36/A 36M. shall be tested full size and shall conform to the requirements for tensile strength specified in Table 3.5 Zinc Coatings. 4.1.1. Philadelphia.5).3 Grade A and B bolts and studs larger than 1½ in.3 Grade. 5.2 Stress relieving of hex head fasteners shall be at the manufacturer’s option.5 Application of heats of steel to which bismuth. 5.1.4 Quantities (number of pieces by size including nuts). if required. New York.. 3.2 When hot-dip is specified.4 Bolts and studs are customarily furnished from stock.05 0. 4 Section D.15 0.4.3 Heat Treatment: 4. 6. other than those excepted in 6.5 Fastener size and length.2 The purchaser shall have the option of conducting product analyses on finished bolts in each lot.7 Zinc Coating—Specify the zinc-coating process required.3 When mechanically deposited is specified. 6.5. max Sulfur.6 Washers—Quantity and size (separate from bolts). 5.1 Grade A and B bolts and studs shall have a heat analysis conforming to the requirements specified in Table 1 based on the steel producer’s heat analysis. in diameter.. selenium. machined specimens shall be tested and shall conform to the requirements specified in Table 4. Materials and Manufacture 4.5. in which case individual heats of steel cannot be identified.04 Product Analysis 0.29 0.4 Grades A and B bolts and studs less than three diameters in length or bolts with drilled or undersize heads are not subject to tensile tests.A 307 – 03 B 18.1.33 0.1.1 When zinc-coated fasteners are required. the purchaser shall specify the zinc-coating process. 3. Class C or a mechanically deposited zinc coating in accordance with Specification B 695. Properties are 4.24. 2 .3) or special requirements. 3. 0 Brinell min Less than 3 3 diaB 3 3 dia and longer Less than 3 3 diaB 3 3 dia and longer All A B C TABLE 4 Tensile Requirements for Machined Specimens Tensile strength. shall be performed at the frequency and quality described in Table 5. Lot Size Sample SizeA. 212 No hardness required min max 69 .1.97 7.022 0.1. Based on 60 ksi (414 MPa).4 The gaging limit for bolts and studs shall be verified during manufacture or use by assembly of a nut tapped as nearly as practical to the amount oversize shown above. B TABLE 3 Tensile Requirements for Full-Size Bolts and Studs Threads per inch Stress Area..969 1. bolts and studs to be used with nuts or tapped holes which have been tapped oversize. ⁄ 5⁄16 . and threads per inch.1419 0.2.0775 0. 18 7.462 8 11 13 20 27 500 000 550 050 700 8 11 13 20 27 500 000 550 050 700 14 18 22 33 46 190 200 600 400 200 14 5 16 12 9 16 1 11⁄8 11⁄4 13⁄8 8 7 7 6 0.155 36 45 58 69 350 800 150 300 36 45 58 69 350 800 150 300 60 76 96 115 600 300 900 500 11⁄2 13⁄4 2 21⁄4 6 5 4½ 4½ 1. nominal diameter of bolt. 833 000 966 000 1 108 000 A Area calculated from the equation: As= 0. 3 . 241 121 212 . min. B 1 lbf = 4. Assembly of the gage.1 Unless otherwise specified. Grade A bolts shall be hex bolts with dimensions as given in the latest issue of ANSI/ ASME B18. shall have Class 2A threads before hot-dip or mechanically deposited zinc coating..405 1.. Dimensions 7.90 2. 6. gage tolerance plus) shall be used. the full-size test shall govern if a controversy between the two methods exists. 11⁄2 13⁄4 to 4.0318 0. and shall have a Class 2A tolerance.2. a calibrated thread ring gage of that same size (Class X tolerance.10 240 295 358 426 000 800 200 000 240 295 358 426 000 800 200 000 400 493 597 710 000 000 000 000 31⁄2 33⁄4 4 4 4 4 8.66 11.182 0. incl 13⁄8 .B Acceptance NumberA 2 to 90 91 to 150 151 to 280 281 to 500 501 to 1 200 1 201 to 3 200 3 201 to 10 000 10 001 and over 13 20 32 50 80 125 200 315 1 2 3 5 7 10 14 21 A Sample sizes of acceptance numbers are extracted from “Single Sampling Plan for Normal Inspection.7854 [D − (0.3 Unless otherwise specified.” Table IIA.017 0.. min ksi Elongation in 2 in.. After zinc coating the maximum limit of pitch and major diameter shall not exceed the Class 2A maximum limit by more than the following amounts: A Bolt Size. threads shall be the Coarse Thread Series as specified in the latest issue of ANSI/ASME B1. B Inspect all bolts in the lot if the lot size is less than the sample size. (mm)A 0. In case of dispute. These inspections. in.0524 0.763 0. incl 7⁄8 1. Grade A stress area. incl 14 A These values are the same as the overtapping required for zinc-coated nuts in Specification A 563. 1⁄2 9⁄16 to 3⁄4 .334 0. ksi Yield point. 100 100 95 95 As measured anywhere on the surface or through the cross section.0 to 11⁄4 . 18 58–80 36 23 Oversize Limit. acceptance based on tensile requirements shall take precedence in the event that there is controversy over low readings of hardness tests. % Rockwell B max 121 241 ..606 0. in.00 4.2 Unless otherwise specified.1063 1 3 4 6 900 100 650 350 1 3 4 6 900 100 650 350 3 5 7 10 180 240 750 630 ⁄ ⁄ 5⁄8 3⁄4 7⁄8 13 12 11 10 9 0.93 5. These sizes and bolts with modified heads shall meet the minimum and maximum hardness as hardness is the only requirement.0.016 0.25 84 114 150 195 300 000 000 000 84 114 150 195 300 000 000 000 140 190 250 325 500 000 000 000 21⁄2 23⁄4 3 31⁄4 4 4 4 4 4. 6. MIL-STD-105.33 9. Grade B bolts shall be heavy hex bolts with dimensions as given in the latest issue of ANSI/ASME B18. in..A in.018 0. D Based on 60–100 ksi (414–690 MPa). 7. C TABLE 5 Sample Sizes and Acceptance Numbers for Inspection of Hot-Dip or Mechanically Deposited Zinc-Coated Threads shown in Table 4 for information. when performed to resolve disputes.. In the event of conflict Specification A 36/A 36M shall control. Also bolts with drilled or undersize heads..6 In the event that bolts are tested by both full size and by machine test specimen methods.. 3⁄8 7⁄16 .020 0. or the nut described above.1. minC Grade B minD maxD ⁄ ⁄ 3⁄8 7⁄16 20 18 16 14 0.50 3.A 307 – 03 TABLE 2 Hardness Requirements for Bolts and Studs Grade HardnessA Length.08 499 800 579 600 664 800 499 800 579 600 664 800 Grade C 60–100 ...2 Tensile Strength.024 0. 7. lbfB Grade A. must be possible with hand effort following application of light machine oil to prevent galling and damage to the gage.226 0.448 N.050 Diameter..9743/n)]2 where: As = D = n = Grade B 60 min . 69 . 7. in accordance with Specification A 563.027 0. Unless otherwise specified. in.7 For bolts and studs on which both hardness and tension tests are performed. all bolt heads. suppliers option. 14. Test Methods 9.1.3 Name and brand or trademark of the manufacturer.1 One type of item.2.2 The inspector representing the purchaser shall have free entry to all parts of the manufacturer’s works that concern the manufacture of the material ordered.2 Grade C Anchor Bolts: 13. (25. All tests and inspections required by the specifi4 .5 If any machined test specimen shows defective machining it shall be discarded and another specimen substituted. 13.1. 13. 8.2 When permanent marking of manufacturer’s identification and grade identification is required.5 Purchase order number. 14. Packaging and Package Marking 14. shall be marked with a grade marking as follows: Number of Samples 1 2 3 5 8.6 Country of origin. they shall be defined at the time of the inquiry and order. Individual heats of steel are not identified in the finished product. 8. and whenever feasible studs less than " in.4 Number of pieces.1 The requirements of this specification shall be met in continuous mass production for stock. one end of studs " in.1 Grades A and B Bolts and Studs: 13.3.1. Additional tests of individual shipments of material are not ordinarily contemplated. Product Marking 13. 8.2 Package Marking: 14.2.2 One nominal size.3 One nominal length of bolts and studs.2 Grade C nonheaded anchor bolts shall have machined specimen tension tests made on the bolt body or on the bar stock used for making the anchor bolts.2. 9. 9. 10. Rejection and Rehearing 12. Number of Tests and Retests 8. packaging shall be in accordance with Practice D 3951.4. the manufacturer shall furnish a test report certified to be the last completed set of mechanical tests for each stock size in each shipment.1 Unless otherwise specified.1 Disposition of nonconforming lots shall be in accordance with Guide F 1470. Inspection 10. 13. The two identifications shall preferably be in different locations and. 14.1.1 Packaging: 14. and purchasers option.2 is required by the purchaser it shall be specified in the inquiry. shall be separated by at least two spaces.2.1 The end of Grade C anchor bolts intended to project from the concrete shall be color coded green.2 Size. in which case all of the additional samples shall meet the specification.1.1. tested and inspected in accordance with this specification and meets all of its requirements. or contract. sampled.2. Grade A B Marking 307A 307B 13.2. a lot.3 Grade and manufacturer’s or private label distributor’s identification shall be separate and distinct. 10. 8.4 mm)/min for the tensile strength tests of bolts.2 In addition to the requirements of 13.3. Additional marking required by the manufacturer for his own use shall be at the option of the manufacturer.1.3 When additional tests are specified on the purchase order.1. shall consist of all material offered for inspection at one time that has the following common characteristics: 8. when on the same level. 9. Responsibility 11. 14. 14. and shall be conducted as not to interfere unnecessarily with the operation of the works.3 Standard square and hex head bolts only shall be tested by the wedge tension method except as noted in 6. Fracture shall be in the body or threads of the bolt without any fracture at the junction of the head and body.1 Each shipping unit shall include or be plainly marked with the following information: 14.1.2. 12. and 8. 13. Supplementary Requirements S2 and S3 shall be specified.3.2 When special packaging requirements are required. 13.1. Tests on finished anchor bolts shall be made in accordance with Test Methods F 606 and tests on bar stock in accordance with Specification A 36/A 36M and Test Methods A 370. 8. 9.6 Should any sample fail to meet the requirements of a specified test.1.2 When specified in the order. 14.3 All markings shall be located on the top of the bolt head or stud end and shall be raised or depressed at the option of the manufacturer. and larger. specifically sections on disposition of nonconforming lots. for purposes of selecting test samples.4 From each lot. 14. order.A 307 – 03 cation that are requested by the purchaser’s representative shall be made before shipment. and the manufacturer shall make sample inspections to ensure that the product conforms to the specified requirements.2.1 If the inspection described in 10.1 Bolt heads and one end of studs shall be marked with a unique identifier by the manufacturer to identify the manufacturer or private label distributor. the number of tests for each requirement shall be as follows: Number of Pieces in Lot 800 and under 801 to 8 000 8 001 to 22 000 Over 22 000 11. 8. as appropriate.4 Speed of testing as determined with a free running crosshead shall be a maximum of 1 in.1 ASTM designation and grade. double the number of samples from the same lot shall be tested. 14.1 The party responsible for the fastener shall be the organization that supplies the fastener to the purchaser and certifies that the fastener was manufactured.1.2. Other headed bolts shall be tested by the axial tension method. The manufacturer shall afford the inspector all reasonable facilities to satisfy him that the material is being furnished in accordance with this specification.1 Grades A and B bolts and studs shall be tested in accordance with Test Methods F 606. 5.06 +0.1 bolts. It is presupposed that suitable welding procedures for the steel being welded and the intended service will be selected.6 Analysis Reports—If requested on the order or contract. Cold-forged bolts.1.5.05 S2.008 +0. Carbon Manganese Phosphorus Sulfur Silicon 0.1 Heat Chemical Analysis—Material conforming to the following additional analysis limitations shall be used to manufacture the product described in this supplementary requirement. this supplemental section is limited to hot-forged bolts.00 %. 0. then to bolts produced from hot-rolled bars without forging or threaded bars.05 %. S1. 0. 1. Keywords 15. or cold-drawn threaded bars.1 The end of the anchor bolt intended to project from the concrete shall be steel die stamped with the Grade identification “307C”.50 %.2 The requirements in S2. consult the anchor bolt manufacturer for the minimum size capable of being marked.1 The end of the anchor bolt intended to project from the concrete shall be steel die stamped with the manufacturer’s identification. if they are given a thermal treatment by heating to a temperature of not less than 1500°F (815°C) and air-cooled are also suitable.7 Product (Check) Verification Analysis—Chemical analyses when made by the purchaser or a representative on bolts from each heat of steel. mechanical.008 +0. Bolts Suitable for Welding S1.03 +0. S1. or stud bolts produced from hot-rolled bars without forging.5. max max max max max S3.3 All of the requirements of this supplemental section apply in addition to all of the chemical. the heat analysis shall be such as to provide a 5 .2 Carbon Equivalent (Source—Specification A 706/ A 706M)—In addition to the heat chemical analysis requirements in S1.4 Because of the embrittling effects of welding temperatures on cold-forged steel. % Mn % Cu % Ni % Cr % Mo % V 6 1 40 1 20 1 10 2 50 2 10 S1. S1. studs SUPPLEMENTARY REQUIREMENTS The following supplementary requirement shall apply only when specified in the purchase order or contract: carbon equivalent (CE) not exceeding 0. or. 0.55 when calculated as follows: CE = % C + S1. This supplemental section. if not forged. the chemical composition of each heat of steel used and the calculated carbon equivalent for each heat shall be reported to the purchaser. shall not exceed the values specified in S1. bars studs. and other requirements of the base specification.5. Permanent Grade Identification S3. S1.30 %.A 307 – 03 15.1 The material described in this section is intended for welding. provides assurance of weldability by chemical composition control.5 Chemical Requirements: S1.1 for marking small sizes shall also apply to Supplementary Requirement S3. S1. by additional chemical composition restrictions and by a carbon equivalent formula.. Specification A 307 for Grade B.2 by more than the following amounts: Carbon Manganese Phosphorus Sulfur Silicon % +0. Permanent Manufacturer’s Identification S2.2 Welding technique is of fundamental importance when bolts produced to this supplementary section are welded. carbon steel. customarily less than " in. S3. S1. NOTE —For marking small sizes.04 %. steel. or both. are entirely their own responsibility. This standard is copyrighted by ASTM International. PO Box C700. at the address shown below. or both. or through the ASTM website (www. For the convenience of the user. 2003. PA 19428-2959. Committee F16 has highlighted those changes that impact the use of this standard. ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. Committee F16 has highlighted those changes that impact the use of this standard. 6 .astm. (Approved Oct. (Approved October 10. and the risk of infringement of such rights. If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards.) (1) Added Section 1.5. West Conshohocken.A 307 – 03 SUMMARY OF CHANGES This section identifies the location of selected changes to this standard that have been incorporated since the A 307 – 02 issue. Your comments will receive careful consideration at a meeting of the responsible technical committee. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters. which you may attend. 2002. either reapproved or withdrawn. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised. 610-832-9555 (fax). Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address or at 610-832-9585 (phone). This section may also include descriptions of the changes or reasons for the changes.6 that references Terminology F 1789 for definitions of terms. This section may also include descriptions of the changes or reasons for the changes. (2) Corrected the carbon equivalent formula for nickel in S1. This section identifies the location of selected changes to this standard that have been incorporated since the A 307 – 00 issue. Users of this standard are expressly advised that determination of the validity of any such patent rights. United States. or
[email protected].) (1) Deleted the metric units from Table 4. 100 Barr Harbor Drive. For the convenience of the user.org). 1.org (e-mail).